A local network, e.g. a home network or an office network, may comprise several inter-connected consumer electronic devices, e.g. personal computers, mobile phones, set-top-boxes and gaming consoles. Electronic devices within a local network can be adapted to communicate with each other e.g. according to DLNA (Digital Living Network Alliance) standard, which allows electronic devices to communicate and share media content with each other, thereby enabling e.g. access of media files residing e.g. on a PC directly on a TV within the e.g. a DLNA home network, without a complicated configuration process.
A DLNA-compatible device is able to communicate with other DLNA-compatible devices within the DLNA network via the Universal Plug and Play (UPnP), which is a network protocol that is capable of establishing communication between DLNA-compatible devices within a DLNA network, without any configuration. By means of the UPnP, a DLNA device is able to e.g. discover and address other available DLNA devices within a DLNA network, and receive a description of their capabilities.
The DLNA-compatible devices within a DLNA network are typically of different types, based on their function in the media distribution and rendering, and the types involve a DMS (Digital Media Storage/Server), a DMP (Digital Media Player), a DMR (Digital Media Renderer), and a DMC (Digital Media Controller). A DMS may be e.g. a PC (Personal Computer) or a NAS (Network Attached Storage), and it is a device that stores media content and makes it available to a wired and/or wireless networked DMP or DMR. A DMP may be e.g. a TV, a stereo, a game console or a mobile phone, and it is a device that is able to find content on a DMS, and provide playback and rendering capabilities. Further, a DMC is a device that locates content on a DMS and plays it on a DMR, and a DMC may be e.g. a PDA (Personal Digital Assistant) or a mobile phone. Finally, a DMR is a device that plays content received from a DMC, and a DMR may be e.g. a TV, an audio/video receiver, a video display or remote speakers.
FIG. 1 illustrates a conventional DLNA network comprising four DLNA compatible devices, i.e. a DMP 5a, a DMR 5b, a DMS 5c and a DMC 5d. The DMC (Digital Media Controller) 5d is able to obtain a file structure from the DMS, and send a specific URL to the DMR, the URL received from the DMS file structure. The DMR 5b is able to connect to the specified URL, which in this case is the DMS 5c itself. Further, the DMP 5d is also able to obtain a file structure from the DMS, and play a link given in the DMS file structure.
An end-user may want to pause a live media session, e.g. for answering the phone, and then resume the watching of the media session after the phone call. Therefore, it would be advantageous to enable a time-shifting of live media content playing on a local network-device, e.g. in a DLNA network. However, a time-shifting of the live media stream is not possible on a local network-device that is not provided with a hard-drive, such as on a DMR (Digital Media Renderer), e.g. a TV. In order to pause the streaming of a live media session, and resume the streaming of the media session at the same position, a DLNA-device, e.g. a DMR, has to query the status from the media server before pausing the streaming, and perform a seek-command in order to resume the playing of the stream. However, even if a media server would support this functionality, a synchronization gap would exist between the instance when the seek-command was read by the media server, and when the streaming was really paused. Moreover, there is no way to stop an inline-frame in the media stream, so the media content will appear garbled for a while after resuming the play-out.
Thus, it still presents a problem to enable a time-shifting of a live media stream playing on a local network-device, e.g. on a DLNA-compatible device of a DLNA network.